Polymer alloys have been developed, in which polymers having different properties (for example, a non-polar rubber and a polar rubber) are mixed to combine superior properties of such polymers.
One of those studied is a polymer alloy having oil resistance and ozone resistance, which is formed by mixing a rubber such as acrylonitrile-butadiene rubber (NBR) superior in oil resistance and inferior in ozone resistance and a rubber such as ethylene-propylene-diene copolymer rubber (EPDM) superior in ozone resistance and inferior in oil resistance.
For example, Patent Document 1 describes a polymer alloy of NBR and EPDM in which a graft copolymer formed by graft-copolymerizing acrylonitrile and styrene with EPDM is added. Patent Document 2 describes a polymer alloy of NBR and a modified EPDM modified with a hydroxy group. Patent Document 3 describes a polymer alloy of a copolymer of acrylonitrile, butadiene, glycidyl acrylate, and so forth, EPDM, and a modified EPDM modified with maleic anhydride.